Tree spray



1 Patented Dec. 2, 1941 SATES TREE SPRAY No Drawing. Application May 26,1938, Serial No. 210,167

8 Claims.

This invention relates to a new and improved method of applyinginsecticidal materials in a finely divided state as suspensoids inwater, and in combination with petroleum as emulsions.

The object of this invention is greatly to increase the insecticidalvalue and efficiency of insecticides that are applied as suspensoids inan aqueous medium, both with or without the addition of petroleum oil.

A further. object of this invention is, from a given concentration ofthe suspensoid in its aqueous medium, greatly to increase the amountdeposited on fruit and foliage, and greatly to reduce the amount in therun-oif.

A further object is, when oil is used in addition to a suspensoid in thewater phase, thus forming an emulsion, to transfer the suspensoid fromthe water to the oil phase of the emulsion and to deposit the same inoil and not in water.

It is well known that the killing efliciency or toxicity to insects ofany insecticide is definitely related to its concentration or to theamount that is deposited per unit area. For example in fumigating withHCN, 20 cc. of liquid HCN per 100 cubic feet has been determined to bethe lethal dosage necessary to kill most scale insects of citrus.Recently the lethal dosage of lead arsenate necessary to control thecodling moth on apples has been found to be 70 micrograms of leadarsenate (20 micrograms AS203) per square centimeter in the EasternStates, and on the Pacific coast 105 micrograms (30 micrograms AS203)per square centimeter on fruit and foliage.

When finely divided substances are applied as suspensoids in water tothe fruit and foliage of the apple by means of a spray, the deposit perunit area increases in proportion to the increase in amount per 100gallons of Water up to a certain optimum, above this point the increasein deposit falls off. In the case of arsenate of lead this optimumamount or concentration is about 3 pounds to the 100 gallons. At bestthis deposit is only a minute fraction of the actual amount of leadarsenate in the spray, and what is more important it is far below theknown lethal dosage, or deposit necessary to control the insect.

For instance at 3 pounds to the 100 gallons, 50 cc. contains 179,856micrograms of lead arsenate, if this amount-50 00., were sprayed evenlyover the surface of an apple with an area of 100 square centimeters(diam; 6 cent), then each square centimeter of surface would hold 1,798micrograms. In actual practice however, most of this meter or fromapproximately one-third to onehalf of the amount known to be the lethaldeposit necessary to control codling moth. This is no doubt one of thereasons for the poor results achieved and for the great number of sprayapplications found to be necessary to keep the codling moth in check, infact the cost of control is becoming prohibitive so that large acreagesof apples are being abandoned.

The use of the usual spreading and wetting agents does not help matters.While a smoother, more even cover is produced, the run-ofi is heavierand the suspensoid is carried away with it, actually leaving less of thesuspensoid deposited over the surface of the fruit than is the case whenno spreading agent is used.

is lost in the run-off, and the actual deposit av- When oil is addedeither as a Knight type soluble (U. S, 1,949,798, 1,949,799, etc.) or asa paste emulsion, the deposit of suspensoid is somewhat increased, butthe increase in efficiency is largely attributable to the ovicidalaction of the oil, The addition of so-called stickers such as fish oil,etc. increases the deposit but slightly,

I have discovered that by the use of certain depositing agents,hereinafter described, the amount of suspensoid deposited on the surfaceof the fruit and foliage may be increased from five to ten times or evenmore, thus making it possible to deposit the insecticide in amountsequalling or exceeding the known lethal density.

When oil is added and emulsified even greater deposit of the suspensoidcan be efiected if the suspensoid can be transferred from the water tothe oil phase of the emulsion, or in other words, can be preferentiallywet'by oil.v This is readily explained when it is remembered that in thefirst instance 3 pounds of suspensoid are dispersed in 100 gallons ofwater. Oil is usually added at from /2% to 1%. Assuming 1% to be theamount, then we have 1 gallon of oil to-l00 gallons of water and 3pounds of suspensoid in the water phase, Now if the suspensoid betransferred to the oil phase then 3 pounds becomes suspended in 1 galloninstead of 100 gallons, or in other words, the concentration isincreased 100 times.

It has been shown in my'co-pending application S. N. 121,044, which hasmatured into Patent No.- 2,190,173 dated Feb. 13, 1940, that underfavorableconditions approximately of the oil content may be made toadhere to the surface sprayed. If this oil now carries the suspensoid,it will be deposited with it in greatly increased amounts per unit area.For example, when cryolite was suspended in water at the rate of 3pounds to the gallons and was sprayed on apples a or over 14 times, andwith phenothiazine it was increased over 8 times.

When the depositing agent is used without oil the deposit is increasedfrom 5 to 6 times or more, but the increase is in both instances (withor without oil) more than double th'e amount of the known lethal depositor density required to effect a kill.

In my previous patents reference was made to certain properties of theesters of the polyhydroxy alcohols and high molecular weight organicacids. It has since been discovered that they have outstandingproperties as wetting and spreading agents for water, as well as oil,producing a smooth even film or cover on the surface sprayed free fromdrops or spots. They also completely and efiectually wet suchsuspensoids as phenothiazine which is very difficult or even impossibleto wet with water alone.

These esters, however, do not ordinarily increase the density of theensuing deposit when used by themselves. On the contrary, in someinstances they tend to diminish the density of the deposit owing toincreased run-off. I have discovered that when a small amount of certainorganic oil-soluble compounds is dissolved in the above-mentionedesters, they exhibit the peculiar and unique characteristic of greatlyincreasing the deposit of a suspensoid from the water phase, and whenoil is present, the equally unique property of transferring thesuspensoid to the oil phase, or of causing it to be wet preferentiallyby oil. I believe this to be due to electrolytic changes brought aboutby the inclusion of these compounds.

When oil is'present the addition of these compounds will bring aboutinversion of the emulsion if not; checked; this is an additional reasonfor ascribing electrolytic causes to the phenomenon since inversion isrecognized to be electrolytic in nature. To offset this tendency andkeep the emulsion in a workable condition (inverted emulsions cannot besprayed), that is, dispersed throughout the aqueous medium, arestraining agent is introduced. This is preferably a mixture ofbentonite and aluminum sulfate 4 parts to 1 part, but other conditioneror restraining agent may be used, as will hereinafter be described. Thistends to keep the oil releasing tendency of the emulsion at its highestpoint, while preventing inversion and in addition provides a smoothermore uniform deposit, which is desirable.

The greatly increased deposits made possible by this technique willenable a substantial reduction to be made both in the amount ofinsecticide used and in the number of applications previously foundnecessary for effective control, thus greatly reducing the cost to thegrower.

The oil-soluble organic compounds which I employ with my esters of highmolecular weight organic acids are preferably compounds of the typerepresented by the following formula: R-N(R')2.X where R is an alkyl,aryl or aralkyl group; R" is hydrogen or an alkyl, aryl or aralkylgroup, and X is a carboxylic acid, substituted or not, having at least 6carbon atoms. A preferred example of such compound is:

Mono-amyl-amine-oleate, CsHnNI-IzCOOHCnHa: Butyl-ainine-naphthenate,CiHQNHQCOOHCtHh Ethyl-amine-stearate. C2H5NH1COOHC1'IH35Methyl-ethyl-amine-oleate,

Triethyl-amine-oleate, (CzI-LsMNCOOHCrzI-Isa Naphthenic acid,oil-soluble naphthenates, naphthenic acid esters, sulfonated animal,vegetable, mineral and fish oils, sulfonated naphth'enic acids, etc. arealso effective as depositing agents, particularly when combined with thesubstituted ammonia (amine) compounds in the form of alkyl, aryl, oraralkyl amine soaps. As is known the above acids are soap forming, i. e.their alkali metal or amine salts are soaps having detergent properties.

In practicing my invention I dissolve the depositing agent (an organicoil-soluble compound of the type hereinabove described) in glyceryloleate or an equivalent ester in proportions of about 1 to 3 to 1 to 20,depending somewhat on the suspensoid to be used and on the particulardepositing agent. I have obtained excellent results by dissolving 1 partof mono-amyl-amineoleate in 5 parts of a glyceryl oleate which is notcompletely esterified, i. e., which contains a considerable amount ofglyceryl di-oleate or glyceryl mono-oleate. Another very effectivemixture is 1 part of an amyl amine soap of sulfonated naphthenic aciddissolved in 20 parts of glyceryl oleate.

The liquid combination as hereinabove described is then used at the rateof from 6 to8 ounces to 100 gallons of water as both wetting anddepositing agent. It is introduced into the spray tank by means of aninjector situated at any convenient point in the circulatory system. Iprefer to use a type of injector operating on the pressure vacuumprinciple which is merely slipped into place after the spray hose hasbeen detached climatic conditions, etc.

for filling. This picks up the wetting and depositing agent and/or oilunder the full pressure of the pump (400 to 500 lbs.) and delivers thesame fully emulsified into'the tank. A suitable formula is as follows:

Arsenate of lead lbs... 3 Depositing agent mixture ....ounces 8 Waterallons 100 by a Saybolt viscosity at 100 F. of about 40 to 100 seconds.The unsulfonatable residue usually ranges from about '10 to 100,depending somewhat upon the type of foliage, kind of parasite, Apreferred oil is a technical white oil having an unsulfonatable residueof about and a viscosity of about 70 seconds Saybolt at F. A suitableformula for an oil spray is as follows:

, Per cent Technical white oil 95.0 Glyceryl mono-, and di'oleates 2.5Mono-amyl-amine-oleate 5 Aluminum nleate 2.0

Total 100.0

CHaChHsNHCOOHCnHa: I

. 2,264,761 Each gallon of the above oil may be emulsified in 50 to 200gallons of water; for most purposes a 1% oil concentration is preferred.The oil is usually introduced into the tank of the spray ring throughthe injector. The insecticide'used with the above spray may be of anyconventional As hereinabove stated, my preferred depositing agent is amixture of an ester of a polyhydroxy alcohol and a high molecular weightorganic acid with a substituted amine soap. I have found that soaps madefrom sulfonated oils and sulfonated naphthenic acid are much moreeffective than ordinary naphthenates, oleates, stearates, etc.Sulfonated mineral oils, or more particularly sulfonated animal orvegetable oils such as sulfonated castor oil, may be used in someinstances without the ammonia or amine compound, using about 1 part ofsulfonated oil or sulfonated oil soap to parts of glyceryl monooleate.One part of sulfonated naphthenic acid may be mixed with parts ofglyceryl monooleate to give a depositing agent which has desirableproperties. If these sulfonated oils or sulfonated naphthenic acids aretreated with the alkyl amines, the resultant soaps are efiective whenused in the proportion ofv 1 part of soap to parts of glycerylmono-oleate.

I have found that with many insecticides it is necessary to employ a.restraining agent to avoid the inversion of the oil-in-water emulsions.I prefer to employ bentonite or a bentonite mixture for this purpose, apreferred example being 4 parts of bentonite and 1 part aluminumsulfate. Where the spray composition contains other polyvalent cations,such as aluminum oleate, the aluminum sulfate may be omitted, but formost purposes I find that a small amount of it is beneficial. I employabout A to 1 pound of bentonite per 100 gallons of oil-in-wateremulsion. The bentonite may bemixed with the inas follows:

, Per cent Light mineral spray oil 96. 0 Glyceryl oleate 2. 0 Aluminumoleate 1. 5 Sulfonated naphthenic acid 0. 5

Total 100. 0-

The above soluble oil is emulsified in 100 gallons of water with theaddition of to 1 pound of bentonite and 3 pounds of lead arsenate,cryolite, or other specific insecticidal material. The sulfonatednaph'thenic acid supplements the glyceryl oleate, transferring theinsecticide to the oil phase and depositing this insecticide in amountsfar in excess of those required for a lethal dosage.

secticide prior to the introduction of the latter The bentonite preventsemulsion difficulties and brings about a flocculent structure whichprevents oil from settling out, holds the insecticide in the dispersedphase with the oil and improves the deposit when applied to plantleaves.

Bentonite is particularly useful when nicotine is employed as aninsecticide, either in oil-soluble or water-soluble form because thebentonite appears to' prevent the loss of nicotine with the run-01fwater or drips. When nicotine or any other toxic material is used whichhas the property of being adsorbed, absorbed or otherwise combined withthe bentonite, the bentonite may be employed in larger quantities thanwould be otherwise indicated. In such cases the amount of g bentonitemay be roughly equivalent to the amount of lead arsenate, cryolite,etc., as set forth in the previous examples. With a 5% solution ofnicotine naphthenate I may use from 2 to 5 pounds of bentonite pergallons. Little or no aluminum sulfate is required with this bentoniteand in any case, from 2 to 3 ounces per 100 gallons is sufiicient. Apreferredmaterialfor use with nicotine consists substantially of PartsBentonite I. 9 Fullers earth 9 Aluminum sulfate 2 this mixture beingapplied at 3 to 5 pounds per 100 gallons of spray.

A formula employing a sulfonated oil depositing agent is:

Per cent Technical white oil 97.0 Glyceryl-mono-oleate 2.5 Sulfonatedcastor oil .5

ammonia compound (preferably a soap) to an ester of a polyhy'droxyalcohol and a high molecular weight organic acid will give a depositingagent which is extremely effective for both aqueous sprays (containingno oil) and oil-in-water sprays. In aqueous sprays this depositing agentshould be used in amounts of about 4 to 12 ounces per 100 gallons ofwater and per 1 to 4, preferably 3, pounds of insecticide. I prefer touse about 3 pounds of insecticide per 100 gallons of water when theinsecticide is lead arsenate, cryolite and the like. When oil is used,the depositing agent should constitute about 3% to 5% by volume of oil.The restrainer, such as bentonite or bentonite aluminum sulfate mixture,should be inamounts of about A; to 1 pound per 100 gallons of spray.

Although I have described my invention in considerable detail, it shouldbe understood that I do not limit myself to any of these details, exceptas defined by the following. claims which should betconstrued as broadlyas the prior art will perml f I claim:

1..Tlie method of increasing the deposit of an insecticide from the oilphase of an oil-in-water emulsion containing said insecticide,comprising spraying said emulsion which in addition to oil. water andinsecticide contains small amounts of each of the following substances:an oil soluble hydroxy ester of a high molecular weight fatty acid witha polyhydroxy alcohol; an oil soluble organic compound comprising a saltcombining a lower alkyl hydrocarbon amine with a fatty acid; and arestraining agent comprising bentonite for preventing inversion of saidemulsion, the amount of said restraining agent being adapted to preventinversion of said emulsion.

2. An improved insecticidal spray oil comprising an oil-in-wateremulsion containing an insecticide, and further containing small amountsof eachof the following substances: an oil soluble hydroxy ester of ahigh molecular weight organic acid with a polyhydroxy alcohol; an oilsoluble fatty compound comprising a salt combining a lower alkylhydrocarbon amine with a fatty acid; and a restraining agent comprisingbentonite for preventing inversion oi said emulsion, the amount oi saidrestraining agent being adapted to prevent inversion of said emulsion.

3. The spray oil of claim 2 in which the polyhydroxy alcohol isglycerine.

4. The spray oil of claim 2 in which the fatty acid is oleic acid.

5. The spray oil of claim 2 in which said salt is monoamylamine oleate.

6. The spray oil of claim 2 in which the: restraining agent is a mixtureor bentonite and aluminum sulfate.

7. The spray oil of claim 2 in which the restraining agent is a mixtureof bentonite and aluminum sulfate in the approximate proportions of 4:1.

8. The spray oil of claim 2 in which said oil soluble organic compoundamounts to 3-5% by volume of the oil contained in said emulsion.

HUGH EIGHT.

